Difluorobrominium tetrafluoroborate

ABSTRACT

The novel compound difluorobrominium tetrafluoroborate and method of preparation thereof consisting of the contacting of boron trifluoride with bromine trifluoride.

I United States Patent [I51 3,645,702 Toy et al. 51 Feb. 29, 1972 {54] DIFLUOROBROMINIUM OTHER PUBLICATIONS TETRAFLUOROBORATE Emeieos et a1., Advances in Inorganic Chemistry and [72] Inventors: Madeline S. Toy, Fountain Valley; William Radiochemistry." P g 274 py Dale A. Cannon, Costa Mesa, both of Calif. 1966) [73] Assignee: The United sums 0' Alarm as Sehg et al., inorganic Chemistry, Vol. 3,page 294(l964).

"Presented by the Secretary the Army Primary ExaminerM. Weissman Filedi y 1968 Attorney-Harry M. Saragovitz, Edward J. Kelly, Herbert Ber! 2 Appl 745 9 4 and Robert P. Gibson [57] ABSTRACT [52] U.S. Cl ..23/367, 149/22, 149/36,

|49/|()9 The novel compound difluorobrominium tetrafluoroborate [5 l} Int. Cl "C0": 35/00, COlb 7/24,C06d 5/00 and method of preparation thereof consisting of the contact- [58] Field of Search ..23/367 ing of boron trifluoride with bromine trifluoride.

I References Cited 2 Claims, No Drawings DIFLUOROBROMINIUM TETRAFLUOROBORATE This invention relates to a novel compound and method of preparation thereof, and more particularly to difluorobrominiurn tetrafluoroborate.

It is an object of this invention to provide and disclose a novel compound having utility as a solid oxidizer component in a propellant system.

Other objects and a fuller understanding of the invention may be ascertained from the following description and claims.

We have prepared difluorobrominium tetrafluoroborate by bubbling gaseous boron trifluoride through liquid bromine trifluoride at room temperature. The rapid initial gas absorption is accompanied by an exothermic reaction. The product is recovered by evaporation to dryness under a vacuum at room temperature.

in the alternative, gaseous boron trifluoride in excess is condensed on top of frozen bromine trifluoride at liquid nitrogen temperature. The mixture is slowly warmed to room temperature. The product is recovered by evaporation to dryness under a vacuum at room temperature.

A white residue having a melting point of 180 C. was obtained. The infrared spectrum of a thin solid film of the product showed a strong broadband in the region 1,020-1, I cm. indicative of the tetrafluoroborate ion. This band was also observed for KBF NaBF RbBF NOBF NO BF NlLBF, and SF BF,. The product was analyzed. Calculated for BrF BF F, 55.69; Br, 39.04 and B, 5.33. Found: F, 55.37 and B, 5.91.

Difluorobrorninium tetrafluoroborate has utility as an oxidiaer component in a rocket propellant in conjunction with a f uel component and a binder. Suitable fuel components within the scope of this invention include pentaborane (B51719), monomethyl hydrazine, hydrazine and unsymmetrical dimethyl hydrazine. Suitable binders include certain natural and synthetic resins, e.g., butadiene-styrene and butadiene' acrylate rubbers. polyesters, phenol-formaldehyde resins. urea-formaldehyde resins, polyacrylates. polyalkylacrylates, polystyrene, polysulfides, polyurethanes and polyvinyl acetate resins.

A specific example of a rocket propellant with the scope of this invention comprises 70 percent oxidizer. l5 percent binder and 15 percent fuel, e.g., 70 percent dilluorobromini um tetrafluoroborate, 15 percent butadiene-styrene rubber and I5 percent pentaborane.

In addition, difluorobrominium tetrafluoroborate has been utilized as a solute in an electrolytic cell to increase the specific conductivity of certain halogen fluorides. Conductivity measurement indicates that difluorobrominium tetrafluoroborate acts as a strong electrolyte in BrF; solution. The specific conductivities of 0.1 mole per liter of solid in BrF, solution at 25 C. was 1.2)(10 ohm cm"' and ca. 0.5 mole per liter in a mixture of BrF and ClF; solution, i.e., 0.83 mole fraction of ClF, in BrF,, was 7.6000 ohm" cm at 60 C.

Although we have described our invention with a certain degree of particularity, it is understood that said disclosure is made to set forth a specific embodiment of the invention and is not intended as a limitation thereof.

Having described our invention, we claim:

1. The novel compound BrF,BF,.

2. A process for the preparation of difluorobrominium tetrafluoroborate comprising the condensation of gaseous boron tritluoride in excess on top of frozen bromine trifluoride at liquid nitrogen temperature, heating the resultant mixture to room temperature and recovering the product. 

2. A process for the preparation of difluorobrominium tetrafluoroborate comprising the condensation of gaseous boron trifluoride in excess on top of frozen bromine trifluoride at liquid nitrogen temperature, heating the resultant mixture to room temperature and recovering the product. 